Coarse Spectra of H & H-like elements explain the basic concept of Electronic Spectroscopy, which explain the possible transitions through selection rule.

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2. A. S. M. Asadur Rahman
Department of Chemistry
Comilla University
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5. Energy contributors-
Attraction between electrons & nucleus
Repulsion between electron's in the same atom
oAs H has one electron interelectronic effect is
absent.
oThus 2s & 2p orbitals are degenerate, however the
energies of 2s, 3s, 4s,… orbitals differ considerably.
Energy of Orbital & H- fact
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6. ℇ� = −
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= −
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(� = �, �, � … )
Energy equation
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7. Selection Rule for H & H like elements
According to Schrodinger equation shows that,
Thus,
1s → np (n ≥ 2)
2p → ns or nd
∆n= anything & ∆l= ±1 only
Hydrogen like elements
The alkali metals, Li, K, Na, Rb and
Cs all have single electron outside a
closed-shell core.
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9. Spectra Representation
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10. 1010Fig: Electronic transitions for H

11. Lyman Series
Discovered By: Harvard physicist Theodore Lyman
Discovered Year: 1906-1914 ( 1st
line in 1906 )
Fig: Representation of part of Lyman
series of the H
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12. Discovered By: Johann Balmer
Discovered Year: 1885
Discovered By: Johann Balmer
Discovered Year: 1885
Balmer Series
Fig: Representation of 1Fig: Representation of 1stst
Balmer lineBalmer line
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